Armytek Prime C2 XP Ink (White) with USB Charged – 18650 Li-ion Rechargeable Battery (3200 mAh) by Magnetic Contact Torch Holster with Clip : Amazon.de: DIY & Tools
D5*2 D5*3 Magnet For 18650 Flat-head Battery - Magnetic Materials - AliExpress
Magnetic Connectors for Batteries : 5 Steps (with Pictures) - Instructables